vala/valaregexliteral.vala

   1 /* valaregexliteral.vala
   2  *
   3  * Copyright (C) 2010  Jukka-Pekka Iivonen
   4  * Copyright (C) 2010  Jürg Billeter
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301  USA
  19  *
  20  * Author:
  21  *      Jukka-Pekka Iivonen <jp0409@jippii.fi>
  22  */
  23
  24 using GLib;
  25
  26 /**
  27  * Represents a regular expression literal in the source code.
  28  */
  29 public class Vala.RegexLiteral : Literal {
  30         /**
  31          * The literal value.
  32          */
  33         public string value { get; set; }
  34
  35         /**
  36          * Creates a new regular expression literal.
  37          *
  38          * @param s      the literal value
  39          * @param source reference to source code
  40          * @return       newly created string literal
  41          */
  42         public RegexLiteral (string value, SourceReference? source_reference = null) {
  43                 this.value = value;
  44                 this.source_reference = source_reference;
  45         }
  46
  47         public override void accept (CodeVisitor visitor) {
  48                 visitor.visit_regex_literal (this);
  49
  50                 visitor.visit_expression (this);
  51         }
  52
  53         public override bool is_pure () {
  54                 return true;
  55         }
  56
  57         public override bool is_non_null () {
  58                 return true;
  59         }
  60
  61         public override string to_string () {
  62                 return value;
  63         }
  64
  65         public override bool check (CodeContext context) {
  66                 if (checked) {
  67                         return !error;
  68                 }
  69
  70                 checked = true;
  71
  72                 if (!context.experimental) {
  73                         Report.warning (source_reference, "regular expression literals are experimental");
  74                 }
  75
  76                 try {
  77                         var regex = new GLib.Regex (value);
  78                         if (regex != null) { /* Regex is valid. */ }
  79                 } catch (RegexError err) {
  80                         error = true;
  81                         Report.error (source_reference, "Invalid regular expression `%s'.".printf (value));
  82                         return false;
  83                 }
  84
  85                 value_type = context.analyzer.regex_type.copy ();
  86
  87                 return !error;
  88         }
  89
  90         public override void emit (CodeGenerator codegen) {
  91                 codegen.visit_regex_literal (this);
  92
  93                 codegen.visit_expression (this);
  94         }
  95 }
  96